feat: multiple UI improvements, font settings, and memory file display names (#175)

## Summary

- **fix**: `show_thinking_blocks` setting now persists across sessions — it was defined on the TypeScript side but missing from the Rust `HikariConfig` struct, so serde silently dropped it on every save/load
- **feat**: Tool calls are now rendered as collapsible blocks matching the Extended Thinking block aesthetic, replacing the old inline dropdown approach
- **feat**: Add configurable max output tokens setting
- **feat**: Use random creative names for conversation tabs
- **test**: Significantly expanded frontend unit test coverage
- **docs**: Require tests for all changes in CLAUDE.md
- **feat**: Allow users to specify a custom terminal font (Closes #176)
- **feat**: Display friendly names for memory files derived from the first heading (Closes #177)
- **feat**: Add custom UI font support for the app chrome (buttons, labels, tabs)
- **fix**: Apply custom UI font to the full app interface — `.app-container` was hardcoded, blocking inheritance from `body`; also renamed "Custom Font" to "Custom Terminal Font" for clarity

✨ This PR was created with help from Hikari~ 🌸

Reviewed-on: #175
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

src-tauri/src/config.rs

@@ -31,6 +31,9 @@ pub struct ClaudeStartOptions {
 
     #[serde(default)]
     pub disable_1m_context: bool,
+
+    #[serde(default)]
+    pub max_output_tokens: Option<u64>,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -126,6 +129,9 @@ pub struct HikariConfig {
     #[serde(default)]
     pub disable_1m_context: bool,
 
+    #[serde(default)]
+    pub max_output_tokens: Option<u64>,
+
     #[serde(default)]
     pub trusted_workspaces: Vec<String>,
 
@@ -135,6 +141,23 @@ pub struct HikariConfig {
 
     #[serde(default = "default_background_image_opacity")]
     pub background_image_opacity: f32,
+
+    #[serde(default)]
+    pub show_thinking_blocks: bool,
+
+    // Custom terminal font settings
+    #[serde(default)]
+    pub custom_font_path: Option<String>,
+
+    #[serde(default)]
+    pub custom_font_family: Option<String>,
+
+    // Custom UI font settings
+    #[serde(default)]
+    pub custom_ui_font_path: Option<String>,
+
+    #[serde(default)]
+    pub custom_ui_font_family: Option<String>,
 }
 
 impl Default for HikariConfig {
@@ -169,9 +192,15 @@ impl Default for HikariConfig {
             discord_rpc_enabled: true,
             use_worktree: false,
             disable_1m_context: false,
+            max_output_tokens: None,
             trusted_workspaces: Vec::new(),
             background_image_path: None,
             background_image_opacity: 0.3,
+            show_thinking_blocks: false,
+            custom_font_path: None,
+            custom_font_family: None,
+            custom_ui_font_path: None,
+            custom_ui_font_family: None,
         }
     }
 }
@@ -286,6 +315,11 @@ mod tests {
         assert!(!config.use_worktree);
         assert!(!config.disable_1m_context);
         assert!(config.trusted_workspaces.is_empty());
+        assert!(!config.show_thinking_blocks);
+        assert!(config.custom_font_path.is_none());
+        assert!(config.custom_font_family.is_none());
+        assert!(config.custom_ui_font_path.is_none());
+        assert!(config.custom_ui_font_family.is_none());
     }
 
     #[test]
@@ -320,9 +354,15 @@ mod tests {
             discord_rpc_enabled: true,
             use_worktree: true,
             disable_1m_context: false,
+            max_output_tokens: Some(32000),
             trusted_workspaces: vec!["/home/naomi/projects/trusted".to_string()],
             background_image_path: Some("/home/naomi/bg.png".to_string()),
             background_image_opacity: 0.25,
+            show_thinking_blocks: true,
+            custom_font_path: Some("/home/naomi/.fonts/MyFont.ttf".to_string()),
+            custom_font_family: Some("MyFont".to_string()),
+            custom_ui_font_path: None,
+            custom_ui_font_family: None,
         };
 
         let json = serde_json::to_string(&config).unwrap();